A so-called mortar mixer can be used to mix solid materials (e.g., sand, gravel, cement) and/or liquids, often at a job site. The term "mortar", as used herein, is intended to mean any type(s) of granular and/or liquid materials, without exception. Manually operating a dump mechanism of a tilt-drum mortar mixer increases in difficulty as the cubic feet of load, or capacity of the drum, is increased. It is, therefore, desirable to use the engine/motor (i.e., the source of power for turning the paddle shaft) to provide power for the dumping of mortar from a tilt-drum, mortar mixer.
Previous designs for powering the dumping of mortar, however, either required the addition of costly gear boxes or power sources, or resulted in lack of precise control of the power mechanism. This imprecision often leads to an over-dumping of mortar, and to unsafe conditions in the operation of the drum. The cost of an additional power source is prohibitive for most masonry contractors.
The present invention seeks to provide a simple, yet precise dumping control for a tilt-drum, mortar mixer. Dumping power is provided by the existing, rotating paddle shaft.
This invention controls the dumping operation of the machine during a dumping cycle. The control system provides a control lever mechanism, which, if accidently released, automatically sets a brake, and nullifies the power transmitted to a pinion pulley. These safety measures cause the drum to stay in its current position, until the control lever can be reactivated.
In addition to safety, the present control system also provides the operator with a good "feel" of the clutch/brake mechanism, effecting precise control. A manual dump lever is retained for use in returning the drum to its mixing position, as a backup in case of belt or engine failure, and as a manual control when cleaning the drum.